Abstract
Tumor gene alterations can serve as predictive biomarkers for therapy response. The nucleotide excision repair (NER) helicase ERCC2 carries heterozygous missense mutations in approximately 10% of bladder tumors, and these may predict sensitivity to cisplatin treatment. To explore the clinical actionability of ERCC2 mutations, we assembled a multinational cohort of 2,012 individuals with bladder cancer and applied the highly quantitative CRISPR-Select assay to functionally profile recurrent ERCC2 mutations. We also developed a single-allele editing version of CRISPR-Select to assess heterozygous missense variants in their native context. From the cohort, 506 ERCC2 mutations were identified, with 93% being heterozygous missense variants. CRISPR-Select pinpointed deleterious, cisplatin-sensitizing mutations, particularly within the conserved helicase domains. Importantly, single-allele editing revealed that heterozygous helicase-domain mutations markedly increased cisplatin sensitivity. Integration with clinical data confirmed that these mutations were associated with improved response to platinum-based neoadjuvant chemotherapy. Comparison with computational algorithms showed substantial discrepancies, highlighting the importance of precision functional assays for interpreting mutation effects in clinically relevant contexts. Our results demonstrate that CRISPR-Select provides a robust platform to advance biomarker-driven therapy in bladder cancer and supports its potential integration into precision oncology workflows.
Authors
Judit Börcsök, Diyavarshini Gopaul, Daphne Devesa-Serrano, Clémence Mooser, Nicolas Jonsson, Matteo Cagiada, Dag R. Stormoen, Maya N. Ataya, Brendan J. Guercio, Hristos Z. Kaimakliotis, Gopa Iyer, Kresten Lindorff-Larsen, Lars Dyrskjøt, Kent W. Mouw, Zoltan Szallasi, Claus S. Sørensen
Figure 1
Extensive analysis of MIBC cohorts.
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)